The open Master Hearing Aid Forum

1) How can I set the input SPL peak level? I mean, if I only have a wav audio file (downloaded from the internet or obtained from anywhere), how can I estimate the input SPL peak level? Is there any preprocessing I can do to normalize or effectively estimate it? Typical hearing aid processing uses ...

2) Regarding post-processing, how should I select the gain value? For example, how did you choose to amplify by -5 or +45 dB as you mentioned? If I am performing automated batch processing (e.g., calculating the amplification for 1000 audio files using NAL-NL2), how can I select or calculate an app...

Thank you for providing a detailed description of your processing steps! This makes it possible to reproduce your experience. 1) I used examples /01-dynamic-compression/1speaker_diffNoise_2ch.wav as my input audio file. 2) I used 94 dB as the acoustic input level in dB SPL. 94 dB SPL peak level is a...

I wanted to be able to build from sources. brew install openmha/tap/openmha is actually compiling openmha from sources on your Mac. We do not provide pre-compiled "bottles" for Mac. I found that OSC was not what I needed to have installed. Instead configure was really looking for libio wh...

The offline fitting tool contained in openMHA preprocesses wav files with a dynamic compression prescription rule of your choice. Start it from Matlab or Octave by invoking mhagui_fitting_offline It can process multiple wav files at once. The installation directory of the openMHA mfiles depends on y...

Hi Florian, thanks for reaching out! 52dB was used for the wide band compression threshold because that value is the default in the NAL NL2 demo software "NAL-NL2 Clinician Edition". You can see this value in the tab "Target Screen" next to the label "Comp. Threshold". ...

Thanks for reporting this behavior! Altering the structure with the mhachain "algos" setting should be possible after cmd=release, then alter the structure, then restart with cmd=start.

I will see how we can modify mhachain in order to improve the error message.

I do not know the afc algorithm very well. There is a good chance that its implementation is still too CPU-hungry to run on the PHL. We usually use a combination of frequency shifting and coherence filtering to achieve feedback suppression in real-time openMHA setups. The afc algorithm stores the op...

Please see https://github.com/HoerTech-gGmbH/openM ... mha.m#L200 for how to feed a buffer of audio to MHAIOParser, and line 203 in this file for how to read the processed result.

If I understand you correctly, then your log on the PHL shows (1) that your nodejs app has actually started, and (2) that your nodejs app reacts to your connection by logging "Cannot get /". If this is not the reaction that you want, then you need to fix this inside your custom nodejs app,...